Question

我的应用程序中有以下查询，以便在将新的拳击手添加到我的数据库时修复任何未知的拳击手ID。为了使系统中的其他查询和功能更容易，添加回合时boxer_1 ID始终小于boxer_2 ID。

以下功能似乎可以完美地更新/切换boxer_1和boxer_2字段，但boxer_1_weight和boxer_2_weight值会得到奇怪的结果，我不能找出原因？

"UPDATE bouts b1, bouts b2 SET b1.unknown_global_id = 0,
                    b1.winner = IF(b2.winner = -3, IF(b1.boxer_1 = 0, '" . $boxer_id . "', b1.boxer_1), IF(b2.winner = -2, IF(b1.boxer_2 = 0, '" . $boxer_id . "', b1.boxer_2), b1.winner)),
                    b1.boxer_1 = IF(b1.boxer_1 = 0, IF('" . $boxer_id . "' > b1.boxer_2, b1.boxer_2, '" . $boxer_id . "'), IF(b1.boxer_1 < '" . $boxer_id . "', b1.boxer_1, '" . $boxer_id . "')), 
                    b1.boxer_2 = IF(b1.boxer_2 = 0, IF('" . $boxer_id . "' < b2.boxer_1, b2.boxer_1, '" . $boxer_id . "'), IF(b1.boxer_2 > '" . $boxer_id . "', b1.boxer_2, '" . $boxer_id . "')),
                    b1.boxer_1_weight = IF(b2.boxer_1 = 0, IF('" . $boxer_id . "' > b2.boxer_2, b2.boxer_2_weight, b2.boxer_1_weight), IF(b2.boxer_1 < '" . $boxer_id . "', b2.boxer_1_weight, b2.boxer_2_weight)),
                    b1.boxer_2_weight = IF(b2.boxer_2 = 0, IF('" . $boxer_id . "' < b2.boxer_1, b2.boxer_1_weight, b2.boxer_2_weight), IF(b2.boxer_2 > '" . $boxer_id . "', b2.boxer_2_weight, b2.boxer_1_weight))
                    WHERE b1.unknown_global_id = '" . (int)$global_id . "'"

boxer_1/boxer_2字段为INT（11），boxer_1_weight/boxer_2_weight字段为十进制（10,1）

例如，如果权重字段以权重186.5和199.7开头，则在运行查询后，它们最终都是239.8，但是拳击手ID是正确的。

Answer 1

您需要一个联接条件，以避免将b1中的所选行与b2中的每一行进行比较。

"UPDATE bouts b1
        JOIN bouts b2 ON b1.bout_id = b2.bout_id
        SET b1.unknown_global_id = 0,
            b1.winner = IF(b2.winner = -3, IF(b1.boxer_1 = 0, '" . $boxer_id . "', b1.boxer_1), IF(b2.winner = -2, IF(b1.boxer_2 = 0, '" . $boxer_id . "', b1.boxer_2), b1.winner)),
            b1.boxer_1 = IF(b1.boxer_1 = 0, IF('" . $boxer_id . "' > b1.boxer_2, b1.boxer_2, '" . $boxer_id . "'), IF(b1.boxer_1 < '" . $boxer_id . "', b1.boxer_1, '" . $boxer_id . "')), 
            b1.boxer_2 = IF(b1.boxer_2 = 0, IF('" . $boxer_id . "' < b2.boxer_1, b2.boxer_1, '" . $boxer_id . "'), IF(b1.boxer_2 > '" . $boxer_id . "', b1.boxer_2, '" . $boxer_id . "')),
            b1.boxer_1_weight = IF(b2.boxer_1 = 0, IF('" . $boxer_id . "' > b2.boxer_2, b2.boxer_2_weight, b2.boxer_1_weight), IF(b2.boxer_1 < '" . $boxer_id . "', b2.boxer_1_weight, b2.boxer_2_weight)),
            b1.boxer_2_weight = IF(b2.boxer_2 = 0, IF('" . $boxer_id . "' < b2.boxer_1, b2.boxer_1_weight, b2.boxer_2_weight), IF(b2.boxer_2 > '" . $boxer_id . "', b2.boxer_2_weight, b2.boxer_1_weight))
        WHERE b1.unknown_global_id = '" . (int)$global_id . "'"

更新两个场对返回奇怪值的值

1 个答案: